1. Field of the Invention
This invention relates to a wound covering for wound treatment. The wound covering overlays the wound area without touching the wound itself. The wound covering preferably controls the temperature, humidity and other aspects of the environment at the wound site.
2. Technical Background
Traditional wound coverings such as bandages are used to mechanically close wounds. Such bandages typically cover and touch the wound. Bandage contact with the wound and can interfere with the healing process.
The benefits of application of heat to a wound are known and documented benefits include: increased cutaneous and subcutaneous blood flow; increased partial pressure of oxygen at the wound site; increased immune system functions, including increased migration of white blood cells to the site.
However, in modern times, heat therapy for the treatment of wounds and infection has been difficult to achieve in practice. Additionally the availability of antibiotics have taken precedence over other therapies for the treatment of wounds and topical infections.
The benefits of controlling other environmental parameters around the wound site are not as well known Controlling the humidity at the wound site as well as the benefits of isolating the wound have not been extensively studied and documented.
The preferred form of the wound covering includes a peripheral sealing ring which, in use, completely surrounds the area of the wound. The upper surface of the peripheral sealing ring is spanned by a continuous barrier layer which is preferably transparent and substantially impermeable. An adhesive and a suitable release liner is applied to the lower surface of the peripheral sealing ring to facilitate the application of the wound covering to the patient""s skin. Once in position, the sealing ring and the barrier layer define a wound treatment volume which surrounds the wound.
In accordance with actively heated embodiments of the invention, the barrier layer may include a pocket adapted to receive an active heater. An alternate form of the invention provides for the transport of heated air from a remote source, to the wound treatment volume. In the active heater embodiments a thermostat and/or a pressure activated switch may be used to control the heating effects of the electrically powered heater. Passively heated embodiments are contemplated as well. These passive versions of the device include the use of thermally insulating coverings which retain body heat within the treatment volume. These reflectors or insulators may be placed in a pocket formed in the barrier layer. Each of these heated embodiments promote wound healing by maintaining the wound site at a generally elevated but controlled temperature.
In general the peripheral sealing ring is made from an absorbent material which may acts as a reservoir to retain and dispense moisture into the treatment volume increasing the humidity at the wound site. The reservoir may also contain-and deliver drugs and the like to promote healing.